Server systems often employ lead-acid batteries and uninterruptable power supplies to allow server devices to ride-through power outages and power disturbances. Batteries contain toxic substances, such as lead and acid electrolyte, and can produce dangerous hydrogen gas during cycling. Additionally, batteries have a limited cycle life and narrow temperature operating ranges that can limit battery performance in environments where server devices are typically employed. For example, temperatures found in data centers that use outside air for efficient cooling can significantly exceed temperature operating ranges for lead-acid batteries impacting battery performance.
Uninterruptable power supplies convert AC power to DC power for storage in batteries, and then convert the stored DC power back to AC power for distribution to server devices. Uninterruptable power supplies are also typically over-designed with reserve capacity dedicated to accommodate occasional spikes in computational demand on a server system. As a result, uninterruptable power supplies are inefficient sources of ride-through power for server devices because of losses associated with redundant power conversion and under-utilized reserve capacity.